5 Answers
5

I just used such a website for an answer here: it doesn't quite offer what you're after, but it's close. In Linguee you can type in a German or an English word; then it gives translations and also sentences from various external sources that provide both a German and an English version of the sentence. The word you're after is marked in yellow so that you can easily find it. However, it seems that the quality of the translation is not always good.

Please be very careful with linguee.com
Be aware that it is just an automated collection of websites that exist in two languages. That means it just collects texts and the corresponding translations - regardless of who (or, indeed, what) made them. Then a computer programme aligns the two langue versions and highlights the elements it thinks likely to belong together.
The result is only useful if you are already very proficient in both languages and can immediately spot whether the translation offered to you is a good one.
The service is supposed to "learn" through the users' participation (grading the results) - but so far this appears to be a very lengthy process. So far the "correctly evaluated" results are a very small minority.
I myself have tried the service frequently since it started and found that the overwhelming majority of hits is not very useful - at best. If you know what you're doing, it may sometimes be helpful for finding alternatives you wouldn't have thought of on your own. For a beginner, using linguee.com could be catastrophic.

bab.la is a language project by Andreas Schroeter and Patrick Uecker.
The idea has been on Andreas' mind for quite some time. During his
high school and university years he lived in Canada, France, Sweden
and the USA. He noticed that just knowing the exact translation often
doesn't really help. You really need to "live" the language to come up
with the right word. Andreas has been collecting dictionaries from
different languages for a long time. Putting the things together was
just a natural step: Starting a portal where language lovers can meet
and exchange their ideas and learn languages from each other. Who is a
better teacher than a native speaker who likes to share his knowledge?
And Patrick is our language expert regarding Pascal, C++, Java,
Prolog, LISP, SQL, PHP, JSP and ASP. Thanks to him and his language
skills this portal is alive today :-)